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Fixed in 2019.1.X

Fixed in 2018.3.X



Found in


Issue ID




[Nested Prefabs] "PPtr cast failed when dereferencing! Casting from PrefabInstance to Prefab!" after upgrading Corridor scene

Scene Management


To reproduce:
1. Download "Corridor Lighting Example" from the Asset Store to 2018.3.0a6 (or any older version);

Observed this issue in 2019.1.0a11.

Steps To Reproduce:

1. Open Unity version 2018.2.0f2.
2. Download and import Tower Defense Template.
3. Load the Menu scene and Run
4. Exit and Open the same project in 2019.1.0a11

2. Close the project and open it with 2018.3.0a7;
3. Open "CorridorDemo" scene;
4. Enter Play mode.

Expected result: Prefabs are upgraded successfully, without any errors.
Actual result: Errors are spammed to the Console: "PPtr cast failed when dereferencing! Casting from PrefabInstance to Prefab!", moving and emissive spheres fall off the screen, the whole scene is dark, even after Generating Lighting.

Reproduced with: 2018.3.0a7, where Nested Prefabs were introduced.
Not reproduced with: 2018.3.0a6.

Fixed in: 2019.1.0a4

Comments (1)

  1. ClayChi

    Sep 13, 2018 14:11

    I tried upgrading my project to 2018.3.(first public beta) it gave PPTR cast failed errors of bunch. When I click to error to see where it's pointing, it was the models directory or model prefabs directory (not the asset itself), but not for all models I believe, some model prefabs only giving same error over an over.

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